1. Field of The Invention
The invention relates to an electric connector, particularly to a Universal Serial Bus (USB) plug connector.
USB connectors are recently developed connectors which can be used to replace most of the input/out (I/O) connectors, for example, D-Sub connectors and Mini-Dins as can be seen in the back of a computer.
2. The Prior Art
Conventionally, a USB plug connector consists of a front shielding shell made of metal, a dielectric body mounted with four contacts, a cable with four leads, and a rear shielding shell. To assemble the connector, firstly, the dielectric body mounted with contacts is mounted in the front shielding shell. Then, the leads are brought to extend into the front shielding shell to be connected to the contacts by a soldering or crimping operation. Finally, the rear shielding shell is connected to the front shielding shell.
The conventional USB plug connector is found to have the disadvantages as set forth below.
Firstly, due to the structural limitation of the front shielding shell, a tool cannot be easily brought into the front shielding shell to approach the contacts to perform the necessary soldering or crimping operation to connect the contacts with the leads.
Secondly, the cable cannot be securely connected to the rear shielding shell, which causes the leads to be easily separated from the contacts when a pulling force is exerted to the cable relative to the connector.
Thirdly, when assembling the front and rear shielding shells, they must be precisely aligned with each other so that locking means formed thereon can be interconnected to securely connect the front and rear shielding shells. Such a requirement brings about that the assembly of the front and rear shielding shells is troublesome and time consuming.
Fourthly, the locking means on the connected front and rear shielding shells can only effectively resist a separating force in a specific direction. This means that the shielding shells may be easily separated from each other when a separating force is applied thereto in another direction.
Finally, the dielectric body cannot be easily and securely mounted into the front shielding shell.
Therefore, an objective of the invention is to provide an electrical connector, particularly a USB plug connector, with a lower shielding shell for receiving a dielectric body therein, wherein the lower shielding shell has a structure which can facilitate an easy approach of a tool thereinto in order to perform a soldering or crimping operation to connect contacts mounted to the dielectric body with leads of a cable.
Another objective of the invention is to provide an electrical connector, particularly a USB plug connector, which has an upper shielding shell connected with a lower shielding shell and a cable having four leads connected to four contacts, wherein the upper shielding shell can firmly connect with the cable so that even if a pulling force is exerted to the cable, the leads thereof will not easily separate from the contacts.
A further objective of the invention is to provide an electrical connector, particularly a USB plug connector, with an upper and lower shielding shell which can be easily assembled, without the necessity to precisely align locking means formed thereon.
Still a further objective of the present invention is to provide an electric connector, particularly a USB plug connector, with an upper and lower shielding shell which can effectively resist a separating force acting on them in either horizontal or vertical direction when they are connected.
Still another objective of the present invention is to provide an electric connector, particularly a USB plug connector, with a lower shielding shell and a dielectric body for mounting a number of contacts, wherein the dielectric body can be easily and securely mounted into the lower shielding shell.